Testing pedestal for radar antenna



June 17, 1952 E. E. MEILSTRUP ETAL 2,600,513

TESTING PEDESTAL FOR RADAR ANTENNA 4 Sheets-Sheet 1 Filed Sept. 28, 1948 /Z .4 v wk m/ a y 41ml WM 7, 5

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ATTORN EY June 17, 1952 E. E. MEILSTRUP ET AL 2,600,513

TESTING PEDESTAL FOR RADAR ANTENNA 4 Sheets-Sheet 2 Filed Sept. 28, 1948 ZZZffiezZsz'rzz v Rosali- 2720, 21%.,

ATTO R N EY June 17, 1952 E. E. MEILSTRUP ET AL 2,600,513

TESTING PEDESTAL FOR RADAR ANTENNA Filed Sept. 28, 1948 4 Sheets-Sheet 3 Z? g 4. 9 v A/ ,r 1/ W A; I

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I ATTORNEY June 17, 1952* E. 5.. MEILSTRUP ET AL 2,600,513

TESTING PEDESTAL FOR RADAR ANTENNA Filed Sept. 28, 1948 4 Sheets-Sheet 4 ATTORN EY Patented June 17, 1952 ilNlTED STATES ATENT GFFEHQE TESTING PEDESTAL FOR RADAR ANTENNA Emil E. Meilstrup and Ross M. Simon, Jr., Winston-Salem, N. 0., assignors to Western Electric Qompany, Incorporated, New York, N. Y., a corporation of New York t pplication September 28, 1 9 i 8, Serial No. 51,603 Claims. (01. 250 3.51)

This invention relates to antenna supports and more particularly to an antenna support that can be adjusted to position a radar antenna at various selected elevations and azimuths.

During the pastfew years the use of radar apparatus has increased immensely because of its wide application in numerous fields. As this use has increased it has become imperative that radar antennas be mounted on supports that are capable of being adjusted to variousdesired azimuths and elevations. This is necessary since complete and adequate test of such antennas require that the antennas be placed in several preselected positions during the course of a test.

It is an object of this inventionto provide an antenna support simple in construction for rapidly adjusting the antenna to desired azimuths and elevations and to provide indicating means for measuring the azimuths and elevations of the antenna in variousselected positions.

In accordance with this and other objects, one embodiment of the invention providesa support comprising a rotatable platform to which an antenna to be tested is secured. This platform is rotatably mounted on a fixed base and has mounted thereto a mechanism for moving the platform about a vertical axis. Through a gear transmission, part of which is mountedon the base and the remainder of which is mounted within a radar unit under test, movementabout a horizontal axis is obtainable. Actuating means in the forms of handwheels are provided to operate the mechanisms to rotate the antenna'to various selected positions. Scales for indicating the degrees of elevation and azimuth to which the antenna is rotated are associated with each of the operating mechanisms.

Other advantages and objects will be apparent from the following detaileddescription taken in conjunction with the drawings wherein;

Fig. 1 is a front elevational'view showingthe antenna support with the .antenna and associated gear case;

Fig. 2 is a top plan viewof the antenna support including a rotatable platform, base, actuating mechanisms and indicating scales, but omitting the antenna and gear case;

Fig. 3 is an enlarged fragmentary sectional view of the swivelmechanism-takenalong the line S3 of Fig. 2, looking in the direction of the arrows;

Fig. 4 is an enlarged fragmentary top plan view of the indicating -.scale mechanism shown generally in Fig. 5 is an enlarged fragmentary sectional view of the indicating scale mechanism and the mechanism for imparting vertical movement to the antenna taken substantially along the line 5 5 of Fig. 4:, looking in the direction of the arrows;

Fig. v6 is a fragmentary sectional View of a portion of the driving mechanism for rotating the antenna platform, which is taken along line 6 6 of Fig. 3;

Fig. 7 is a top plan view showing the gear mechanism for imparting vertical movement to theantenna;

Fig. 8 is a'perspective viewshowing the mounting cf the dual cam.

Referring now to the drawings, Fig. .1 illustrates a base generally designated by the reference numeral II, this base includessix pieces of angle iron [2 welded together to form a hexagonal shaped structure it (Fig. 2). At each of the six cornersof the structure [3 there is weldedone end of one of six angle irons ifljthe otherends of which are welded toand-serve to support a stationary p 1atform l5. Positioned within an aperture 16 of the stationaryplatform l5 and permanentl secured therein is a center post lliof tubular shape. A rectangular frame It, surrounding the center post I! but notsecured thereto, is supported on the stationary platform l5 by meansof a thrust bearing 19 so that rotary movement may be impartedto ,the

frame abouta vertical axis. Rigidly secured to therectangular frame I8 by any suitable means,

such as welding, is a rotatable platform 26 to which a radar unit generally designated bythe reference numeral2l is secured fortest purposes. Providing additional support for the platform 2,9 are four metal strutst22 which are welded to the underside of the outer edge of the plateform 20 and t the rectangular frame [81in the proximity of the thrust bearingv L9.

A wave guide 25 positioned withinvthe center post if, is connected toan outside radar pulse prodncing generator (not shown) and isj'positionedat the top of thecenter postl'l by aretamer plate .21. The wave guide25 is connected withan antennaZBof radar unit 2! byaflexible cable ZS. The fiexibilityof the cableZQfenables theantennaZ S to turn with the. rotatable platform gdwhile the Wave uideZB remains stationary within the center post ll. Thewave guide 25 is used for the purpose of transmitting radar pulses from the generator to the radar antenna 2 8 under test mountedindirectly on the o eia l rl if r l l Welded to and forming a part of the base II is a pair of brackets one of which is shown in Fig. 1 and connecting the two brackets together is a cross member 3| to which is welded a swivel bracket 32 (Fig. 3). As shown in Fig. 3 there is positioned within the swivel bracket 32 a bored swivel block 33 having a shaft 34 passing therethrough. The swivel block 33 pivots about a pair of set screws 35 and 35 which are threaded through a pair of threaded apertures in the swivel bracket 32 to pivotally engage a pair of recesses 31 and 33 in the swivel block 33. The set screws 35 and 33 are each provided with a jam nut 39 to hold the set screws 35 and 36 in an adjusted position. Axial movement of the shaft 34 within the swivel block 33 is prevented by means of a pair of collars 40 and 4| which are secured to the shaft 34 by pins 42 and 43. Permanently pinned to the right end of shaft 34 is a handwheel 44 and the left end of this shaft is threaded to engage an internally threaded swivel block 45 positioned within the rectangular frame I8. Secured to the inside bottom portion the rectangular frame I3 is a swivel bracket 45 having a pair of set screws 47 and 48 threaded therethrough to pivotally engage a pair of recesses 49 and 53 in the internally threaded swivel block 45. In the two side walls of the rectangular frame I8 there is provided a pair of horizontal elongated slots 5I and 52 for the purpose of allowing the shaft 34 to pivot about the set screws 4'! and 48 without binding against the frame I3.

Inasmuch as the swivel bracket 46 is located offset of the axis of rotation of the frame I8, any movement of the swivel bracket 46, such as caused by the turning of threaded shaft 34 in the threaded swivel block 45, results in rotation of the frame I3.

To obtain horizontal angular movement of the radar antenna, the handwheel 44 is turned, thus the threaded shaft 34 moves the swivel block 45 axially of the shaft 34 and as axial movement of the shaft 34 is prevented by pinned collars 43 and 4|, the movement of the swivel block 45 causes the rectangular frame I8 to rotate about the center post I! and carry with it the platform 29 to which the radar unit 2I is secured.

After the desired horizontal rotation is obtained, the rotatable platform 20 can be locked in position by means of a locking device 53 consisting of a nut 54 and a screw 55 having a knurled knob 56. The screw 55 passes through a pair of corresponding arcuate slots (not shown) located in a flanged section 57 of the rectangular frame I8 and in the stationary platform I3. Therefore, when the nut 54 is drawn upon the screw 55 by turning the knurled knob, the flange 51 is brought into binding engagement with the stationary platform IE to prevent any further movement of the flange 51 and rectangular frame I8 relative to the stationary base II.

The brackets 30 are also connected together by means of a second cros member 60 to which is secured an arcuate scale 6| (Figs. 1, 2 and 4) for the purpose of measurement of horizontal angular movement. A vernier 62 (Figs. 4 and 5) fastened to a mechanism housing 63 which in turn is secured to the rotatable platform 20 serves as an indicator for the scale GI and also provides a means to give a more exact reading of the horizontal angular movement.

The mechanism housing 63 (Figs. 1 and 5) consists of a plurality of sections welded together to form a housing for the operating mechanism and indicating scales of the antenna elevating apparatus. A shaft 65 (Fig. 5) having a crank type handwheel 55 secured to one end is journaled in the housing 63 by means of bearings 61 and 68 mounted in the housing 63. To prevent axial movement of the shaft 65 relative to the housing, three collars 69, I0 and 1| are pinned to shaft 85 abutting the bearings 61 and 68 and the housing 63. Positioned between the bearings 67 and 68 and keyed to the shaft 65 is a worm gear 72 engaging a spur gear 13 through which a shaft 74 is slidably mounted. A suitable key 75 in the form of a set screw projects into an elongated longitudinal keyway 15 to prevent rotation of the shaft 14 relative to the spur gear I3 but permits the shaft I4 to move transversely of the spur gear 13. The shaft 14 is journaled within the housing 53 by means of a plain bearing 11 and a plain bearing 18 mounted in the rotatable platform 29. Fixed to one end of this shaft 14 is a circular flange 19 (Fig. l) which is adapted to be engaged by the periphery surface of dual cam 80. Passing through an aperture in the cam and rigidly keyed thereto is a shaft SI having a handle 82 secured at one end thereof. This shaft is journaled within a pair of bearings 83 and 84 mounted in a pair of brackets 85 and 85 (Figs. 1 and 8) which are secured to the mechanism housing 33. The opposite end of shaft 14 is splined to form a gear 8'! to mesh with an internal socket gear 38 contained in a hollow shaft 89 which is part of the radar unit 2 I.

It is through the shaft 14 that motion is transmitted to the radar unit 2I to control an elevat ing mechanism contained therein. Thus if the cam 80 is in the position as shown in Fig. l the high spot of the cam engages the circular flange '73 to hold the splined gear 81in engagement with the internal socket gear 88 of the radar unit. However, if the radar antenna is in the proper elevation and it is desired that further accidental elevation of the radar antenna is to be prevented, then the handle 32 is turned causing the shaft 14 and the flange 19 to follow the contour of the cam 83 thus disengaging the splined gear 81 from the internal socket gear 88 of the radar unit 2 I.

The gear train through which the elevation of the antenna 28 is adjusted by a rotation of the splined gear 81 is shown in Figs. 1 and '1. The transmission of motion within the radar unit 2| may be traced from the socket gear 88 through the shaft 89 to a bevel gear 90 secured to the end of shaft 89 to a mating bevel gear 9! secured to one end of a shaft 92, through the shaft 32 to a bevel gear 93 secured to the opposite end of the shaft 92, to a mating bevel gear 94 secured near the center of a shaft 95, through the shaft 35 to a pair of bevel gears 35 and 97 secured to each end of the shaft 95, to a pair of mating bevel gears 38 and 99 each of which are secured to one end of shafts I55 and IOI, through the shafts I00 and IIJI, to a pair of bevel gears I02 and I I33 secured to shafts I03 and II, respectively, to a pair of mating bevel gears I04 and I05 each of which are secured to an end of a shaft I36 and finally to the radar antenna 28 which is secured to the shaft I33.

The shaft 89 (Fig. 1) is mounted within a casing I08 by means of a bearing H0. The remaining shafts 32, 95, I00, IIlI and I05 (Fig. '7) forming part of the radar unit 2I are each mounted within bearings fixed within brackets III and H2; H3, H4, H5 and H5; H1 and H8; H9 and I20; I2I and I22, respectively, which are in turn rigidly secured to the housing of the radar unit 2 I.

Referring to Figs. 4 and 5, a mechanism 112G for indicating the degree of elevation of the radar antenna 28 is disclosed as being contained within the housing 53. The indicating mechanism I24 consists of a hub I25 mounted on the shaft 54 and positioned thereon by means of a washer I26 resting on top of a hub I21 of gear I3. Secured to the hub I26 is a pinion I28 having a suitable key (not shown) which engages the keyway 15 to prevent rotative movement of the pinion 128 and the hub I21 relative to the shaft Hi. This combination key and keyway allows axial movement of the shaft 74 with respect to the pinion I28 in a manner similar to that described in regard to gear i3 and shaft is. The pinion E28 drives a gear I29 secured to a rotatable pin I39 journaled in a plate I3I. This plate is apertured to fit the hub I25 and is positioned thereon by a flange I32. In order to prevent the plate I3l from rotating with the hub I25, the plate is secured to a projecting section I33 of the housing 63 by means of a pair of machine bolts I34 and E35. Positioned between the gear I29 and the plate I3I is a pinion I36 secured on the rotatable pin I3ii and in meshing engagement with a gear I37. This gear I31 has a hub I33 which is mounted for rotation in a bearing ILQ located in an aperture in the plate I3I.

To the hub I38 of gear I3! a scaled disc lit for indicating the degree of elevation of the radar antenna 28 is secured by means of a locating pin MI and a fiat headed screw I42. The plate I3l has an elongated slot I43 therein for the purpose of viewing the indicia Hi4 (Fig. l) on the disc I 58. A pointer I 55 secured to the plate I3I has one end projecting into the elongated slot I44, for the purpose of facilitating an exact reading of the indicia I44 of the scaled disc lit. In order that a more accurate reading can be obtained, an auxiliary scaled disc I46 (Fig. 5) secured directly to a flange I l! on hub IE5 is provided so as to move in conjunction with scaled disc l ll to give readings in minutes. The plate I3! is provided with an additional slot I 38 into which the other end of pointer I45 projects so that exact readings in minutes of the elevation of the radar antenna 28 can be obtained. Thus by taking simultaneous readings on the scaled disc I43 and the scaled disc I46 exact changes in the elevation of the radar antenna '28 can be obtained in degrees and minutes.

In the embodiment of the invention disclosed, the gearing of the indicating mechanism is selected so that the disc scale Hi0 rotates in a ratio of 6:1 with respect to the rotation of the shaft Hi6 of the radar antenna 28. The disc scale I40 is provided with 60 equally spaced markings about the outer edge so that for every degree change in the elevation of the antenna 28 the disc makes /60 of a revolution and gives a reading of one degree. The large disc I46 is divided in to sextants each of which are provided with 60 equally spaced markings at the outer edge. Thus for each degree that the antenna is elevated the large disc makes /6 of a revolution to indicate a 60 minute change in elevation. It is to be understood that the particular gearing combinations described are merely illustrative, and that numerous other combinations can be employed to give identical or more exact readings than the one shown and described.

It is to be understood that the above-described arrangements of structures and mechanisms are simply illustrative of the application of the principles of the invention. Numerous other arrangements may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. In a testing device for a radar antenna, a base, a platform rotatably mounted on the base, means for mounting a radar antenna on the platform, a spline gear slidably mounted with respect to the platform, a gear train mounted on the platform to rotate the radar antenna about a horizontal axis, a cam mounted on the platform for selectively moving the spline gear into and out of engagement with the gear train, means for rotating the spline gear to actuate the gear train, a swivel having a threaded aperture therein, said swivel secured to the platform and offset from the axis of rotation thereof, a second swivel having an aperture therein secured to the base, a threaded shaft passing through the second apertured swivel to engage the threaded swivel, and means to rotate the shaft to move the threaded swivel toward the second swivel to rotate the platform about a vertical axis.

2. In a testing device for a radar antenna, a base, a rotatable platform mounted on the base, a device to be tested mounted on the rotatable platform, a first swivel secured to the platform and offset from the axis of rotation thereof, a second swivel secured to the base, means interconnecting the swivels for moving the first swivel toward the second swivel whereby the platform is rotated about a vertical axis, a gear train mounted on said platform, a drive mechanism mounted on the platform, and means to selectively engage the drive mechanism with the gear train to rotate the antenna about a horizontal axis.

3. In a testing device for a radar antenna, a base, a rotatable platform mounted on the base, a device to be tested mounted on the rotatable platform, a first swivel mounted on the platform and offset from the axis of rotation thereof, a second swivel mounted on the base, means interconnecting the swivels for moving the first swivel axially along the interconnecting means toward the second swivel whereby the platform is rotated about a vertical axis, a gear train mounted on said platform, a drive mechanism mounted on the platform, cam means for selectively engaging the drive mechanism with the gear train to rotate the antenna to be tested about a horizontal axis, and indicating means for measuring the extent of vertical and horizontal movement.

4. In a testing device for a radar antenna, a base, a platform rotatably mounted on a base, means for mounting a radar antenna on the platform, a spline gear slidably mounted with respect to the platform, a gear train mounted on the platform to rotate the radar antenna about a horizontal axis, a cam mounted on the platform for selectively moving the spline gear into and out of engagement with the gear train, means for rotating the spline gear to actuate the gear train, a swivel having a threaded aperture therein, said swivel secured to the platform and offset from the axis of rotation, a second swivel having an aperture therein and secured to the base, a threaded shaft passing through the second apertured swivel to engage the threaded swivel, means to rotate the shaft to move the threaded swivel toward the second swivel to rotate the platform about a vertical axis, and indicating means for measuring the extent of vertical and horizontal movement.

5. In a testing mount, a stationary support, a rotatable platform mounted on the stationary support, a device to be tested mounted on said rotatable platform, means to rotate the platform about a vertical axis comprising a first swivel mounted on the rotatable platform and ofiset from the center of rotation thereof, a second swivel mounted on the base, means interconnecting the swivels for moving the first swivel toward the second swivel whereby the platform is rotated, means to lock the rotatable platform to the stationary support when a predetermined position is attained, and means to selectively disengage the means which rotates the device about a horizontal axis, the operation of said disengaging means being independent of the position of said device.

EMIL E. MEILSTRUP. ROSS M. SIGMON, J R.

REFERENCES CITED The following references are of record in the file of this patent:

Number 8 UNITED STATES PATENTS Name Date Jackson Nov. 9, 1880 Thomas May 10, 1921 Schwab Dec. 13, 1927 Prieur Feb. 5, 1929 Leib Oct. 31, 1933 Pattensteiger July 2, 1935 Niemeyer Mar. 25, 1941 Williams Sept. 30, 1941 Eaton Dec. 8, 1942 Land June 27, 1944 Link L Aug. 29, 1944 Langstroth Sept. 10, 1946 Lundy Sept. 10, 1946 Langstroth Nov. 12, 1946 Maybarduk Nov. 12, 1946 Edwards Feb. 11, 1947 C'hubb Feb. 18, 1947 King Sept. 9, 1947 Lear May 10, 1949 Moseley Aug. 16, 1949 

